The BFILE datatype in Oracle PL/SQL is used to store binary large objects (BLOBs) in external files. This type of datatype is different from the BLOB datatype in that BLOB data is stored in the database itself, whereas BFILE data is stored outside the database in a file system.
A BFILE column is used to store a reference to an external binary file, and it can be used to store images, audio, video or other binary data. The actual data is stored outside the database in a file system and is accessed using a file name. This means that the BFILE column contains a file locator that points to the actual binary data stored in the file system.
One advantage of using the BFILE datatype is that it enables the database to manage large binary objects more efficiently. Since the actual data is stored in the file system and not in the database, the database can be optimized for processing and managing the metadata, or data about the binary objects, without having to manage the actual binary data. This can help reduce the amount of space required for the database and can improve database performance.
The BFILE datatype can be used in SELECT, INSERT, UPDATE, and DELETE statements in the same way as other datatypes. You can also use the BFILE datatype in procedures and functions, as well as in database triggers and PL/SQL packages.
To use the BFILE datatype in a table, you must first create a directory object that represents the file system directory where the binary files are stored. Then, you can create a BFILE column in the table, and specify the directory object as the source of the binary data.
In conclusion, the BFILE datatype in Oracle PL/SQL provides an efficient way to manage binary large objects stored in external files. This type of datatype can be used in a variety of database operations, and it can help to optimize database performance and reduce storage requirements.